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Optimized parameters of downhole all-metal PDM based on genetic algorithm

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Petroleum Science 2024年第4期21卷 2663-2676页

作者： jia-Xing lu Ling-Rong Kong Yu Wang Chao Feng Yu-Lin Gao China University of Geosciences (Beijing) Key Laboratory on Deep Geo-Drilling Technology of Ministry of Natural Resources

Currently, deep drilling operates under extreme conditions of high temperature and high pressure,demanding more from subterranean power motors. The all-metal positive displacement motor, known for its robust performance, is a critical choice for such drilling. The dimensions of the PDM are crucial for its performance output. To enhance this, optimization of the motor's profile using a genetic algorithm has been undertaken. The design process begins with the computation of the initial stator and rotor curves based on the equations for a screw cycloid. These curves are then refined using the least squares method for a precise fit. Following this, the PDM's mathematical model is optimized, and motor friction is assessed. The genetic algorithm process involves encoding variations and managing crossovers to optimize objective functions, including the isometric radius coefficient, eccentricity distance parameter,overflow area, and maximum slip speed. This optimization yields the ideal profile parameters that enhance the motor's output. Comparative analyses of the initial and optimized output characteristics were conducted, focusing on the effects of the isometric radius coefficient and overflow area on the motor's performance. Results indicate that the optimized motor's overflow area increased by 6.9%, while its rotational speed reduced by 6.58%. The torque, as tested by Infocus, saw substantial improvements of38.8%. This optimization provides a theoretical foundation for improving the output characteristics of allmetal PDMs and supports the ongoing development and research of PDM technology.

关键词： Positive displacement motor Genetic algorithm Profile optimization Matlab programming Overflow area

Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system

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Nuclear Science and Techniques 2024年第2期35卷 222-233页

作者： Jing-Lei Huang Guo-Bin jia Li-Feng Han Wen-qian Liu Li Huang Zheng-Han Yang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power *** model considers the impact of thermal properties of fluid variation on accuracy and has been validated with *** study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet ***,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also *** results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial *** simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability.

关键词： Molten salt reactor Combined cycle Dynamic characteristic Control

Au nanoclusters anchored on TiO_(2) nanosheets for high-efficiency electroreduction of nitrate to ammonia

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Nano Research 2024年第3期17卷 1209-1216页

作者： Miaosen Yang Tianran Wei jia He qian Liu Ligang Feng Hongyi Li Jun luo Xijun Liu School of Chemical Engineering Northeast Electric Power UniversityJilin 132012China Nanchang Institute of Technology Nanchang 330044China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsSchool of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004China Institute for New Energy Materials and Low-Carbon Technologies School of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Institute for Advanced Study Chengdu UniversityChengdu 610106China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Guangzhou Panyu Polytechnic Guangzhou 511483China ShenSi Lab Shenzhen Institute for Advanced StudyUniversity of Electronic Science and Technology of ChinaLonghua DistrictShenzhen 518110China

Electrocatalytic nitrate reduction reaction(NO_(3)RR)offers a unique rationale for green NH_(3) synthesis,yet the lack of high-efficiency NO_(3)RR catalysts remains a great *** this work,we show that Au nanoclusters anchored on TiO_(2) nanosheets can efficiently catalyze the conversion of NO_(3)RR-to-NH_(3) under ambient conditions,achieving a maximal Faradic efficiency of 91%,a peak yield rate of 1923μg·h^(-1)·mgcat.-1,and high durability over 10 consecutive cycles,all of which are comparable to the recently reported metrics(including transition metal and noble metal-based catalysts)and exceed those of pristine TiO_(2).Moreover,a galvanic Zn-nitrate battery using the catalyst as the cathode was proposed,which shows a power density of 3.62 mW·cm^(-2) and a yield rate of 452μg·h^(-1)·mgcat.-*** simulations further indicate that the atomically dispersed Au clusters can promote the adsorption and activation of NO_(3)-species,and reduce the NO_(3)RR-to-NH_(3) barrier,thus leading to an accelerated cathodic *** work highlights the importance of metal clusters for the NH_(3) electrosynthesis and nitrate removal.

关键词： NH3 electrosynthesis Zn-nitrate battery Au nanoclusters nitrate reduction reaction(NRR) TiO_(2)nanosheets

Nanoscopic tribological characteristics of a cryogenically cycled Zr-based metallic glass

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 113-126页

作者： qian jia Qiaosheng Xia Qing Zhou Yucheng Wang Yue Ren Yu Meng Haifeng Wang Feng Zhou State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Surface Engineering and Remanufacturing Xi’an UniversityXi’an 710065China State Key Laboratory of Solid lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Optimized macroscopic tribological behavior can be anticipated in metallic glasses(MGs)by cryogenic cycling treatment(CCT),which is attributed to enhanced ***,the intrinsic friction mechanisms of MGs induced by cryogenic rejuvenation are still poorly *** the present study,nanoscopic wear tests were conducted on the Zr-based MGs surface with different CCT cycles using atomic force microscopy(AFM).After CCT treatment with 100 cycles,the MG displays the highest adhesion and ploughing frictions,but significantly improved anti-wear *** tests and molecular dynamics simulations disclose that the increased adhesion is attributed to the dominance of liquid-like regions in the CCT-treated MGs,and the impact of reduced hardness and weak elastic recovery results in the deteriorated ploughing *** enhanced plasticity effectively dissipates the strain from the AFM tip through multiple shear bands and weakens the adhesion during deformation,giving rise to excellent wear *** study elucidates the promoting effect of CCT on the outstanding antiwear performance of MGs,and is helpful for the development of novel alloys.

关键词： metallic glasses cryogenic cycling treatment nanoscope wear friction mechanism

All-dielectric terahertz metasurface governed by bound states in the continuum with high-Q factor

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 44-54页

作者： Li Kun Zhao Xu Wang Meng jia Xingning Zhao Ruiqi lu Guizhen School of Integrated Circuit Science and Engineering Tianjin University of TechnologyTianjin 300384China School of Electronic and Electrical Engineering Ningxia UniversityYinchuan 750021China QIlu Aerospace Information Research Institute Chinese Academy of Sciences(CAS)Jinan 250101China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing 100024China

The method of terahertz(THz)resonance with a high-quality(high-Q)factor offers a vital physical mechanism for metasurface sensors and other high-Q factor ***,it is challenging to excite the resonance with a high-Q factor in metasurfaces with proper sensitivity as well as figure of merit(FOM)***,an all-dielectric metasurface composed of two asymmetrical rectangular blocks is *** and silicon are the materials applied for the substrate and cuboids *** distinct resonance governed by bound states in the continuum(BIC)is excited by forming an asymmetric cluster by a novel hybrid method of cutting and moving the *** investigation focuses on analyzing the transmission spectra of the metasurface under different variations in structural parameters and the loss of silicon refractive *** the proposed defective metasurface serves as a transmittance sensor,it shows a Q factor of 1.08×10^(4)and achieves an FOM up to 4.8×10^(6),which is obtained under the asymmetric parameter equalling 1μ***,the proposed defective metasurface is sensitive to small changes in refractive *** the thickness of the analyte is 180μm,the sensitivity reaches a maximum value of 578 GHz/***,the proposed defective metasurface exhibits an extensive number of possible applications in the filters,biomedical diagnosis,security screening,and so on.

关键词： terahertz(THz)metasurface high-quality(high-Q)factor bound states in the continuum figure of merit(FOM)

AGK2 pre-treatment protects against thioacetamide-induced acute liver failure via regulating the MFN2-PERK axis and ferroptosis signaling pathway

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 43-51页

作者： Qing-Qi Zhang qian Chen Pan Cao Chun-Xia Shi lu-Yi Zhang lu-Wen Wang Zuo-Jiong Gong Department of Infectious Diseases Renmin Hospital of Wuhan UniversityWuhan 430060China

Background:Acute liver failure(ALF)is an unpredictable and life-threatening critical *** pathological characteristic of ALF is massive necrosis of hepatocytes and lots of inflammatory cells infiltration which may lead to multiple organ ***:Animals were divided into 3 groups,normal,thioacetamide(TAA,ALF model)and TAA+*** L02 cells were divided into 5 groups,normal,TAA,TAA+mitofusin 2(MFN2)-siRNA,TAA+AGK2,and TAA+AGK2+MFN2-siRNA *** liver histology was evaluated with hematoxylin and eosin staining,inositol-requiring enzyme 1(IRE1),activating transcription factor 6β(ATF6β),protein kinase R(PKR)-like endoplasmic reticulum kinase(PERK)and phosphorylated-PERK(p-PERK).C/EBP homologous protein(CHOP),reactive oxygen species(ROS),MFN2 and glutathione peroxidase 4(GPX4)were measured with Western blotting,and cell viability and liver chemistry were also *** endoplasmic reticulum membranes(MAMs)were measured by ***:The liver tissue in the ALF group had massive inflammatory cell infiltration and hepatocytes necrosis,which were reduced by AGK2 *** comparison to the normal group,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+in the TAA-induced ALF model group were significantly increased,which were decreased by AGK2 *** levels of MFN2 and GPX4 were decreased in TAA-induced mice compared with the normal group,which were enhanced by AGK2 *** with the TAA-induced L02 cell,apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+were further increased and levels of MFN2 and GPX4 were decreased in the MFN2-siRNA ***2 pre-treatment decreased the apoptosis rate and levels of IRE1,ATF6β,p-PERK,CHOP,ROS and Fe2+and enhanced the protein expression of MFN2 and GPX4 in MFN2-siRNA treated L02 *** observation showed that level of MAMs was promoted in the AGK2 pre-treatment group when compared with the TAA-induced gr

关键词： SIRT2 inhibitor AGK2 Acute liver failure MFN2 Ferroptosis

Efficacy and safety of Yiqi Peiyuan granules for improving the short-term prognosis of patients with acute kidney injury:A multicenter,double-blind,placebo-controlled,randomized trial

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Journal of Integrative Medicine 2024年第3期22卷 279-285页

作者： jia-jia Wu Tian-yi Zhang Ying-hui Qi Min-yan Zhu Yan Fang Chao-jun Qi Li-ou Cao Ji-fang lu Bo-han lu lu-min Tang jian-xiao Shen Shan Mou Department of Nephrology Molecular Cell Lab for Kidney DiseaseShanghai Peritoneal Dialysis Research CenterUremia Diagnosis and Treatment CenterRenji Hospital Affiliated to Shanghai Jiaotong University School of MedicineShanghai 200127China Department of Nephrology Shanghai Pudong New Area Punan HospitalShanghai 200125China Department of Nephrology Ningbo Hangzhou Bay HospitalNingbo 315336Zhejiang ProvinceChina

Background:Yiqi Peiyuan(YQPY)prescription,a composite prescription of traditional Chinese medicine,has been used to prevent or delay the continued deterioration of renal function after acute kidney injury(AKI)in some institutions and has shown considerable ***:This is the first randomized controlled trial to assess efficacy and safety of YQPY for improving short-term prognosis in adult patients with ***,setting,participants and interventions:This is a prospective,double-blind,multicenter,randomized,and placebo-controlled clinical trial.A total of 144 enrolled participants were randomly allocated to two groups according to a randomization ***,caregivers and investigators assessing the outcomes were blinded to group *** in the YQPY group received 36 g YQPY granules twice a day for 28 *** in the placebo group received a placebo in the same dose as the YQPY *** outcome measures:The primary outcome was the change in the estimated glomerular filtration rate(eGFR)between baseline and after 4 and 24 weeks of *** secondary outcomes were the change of serum creatinine(Scr)level between baseline and after treatment,and the incidence of endpoint events,defined as eGFR increasing by more than 25%above baseline,eGFR>75 mL/min per1.73 m2or the composite endpoint,which was defined as the sum of patients meeting either of the above ***:Data from a total of 114 patients(59 in the YQPY group and 55 in the control group)were *** mean changes in eGFR and Scr in weeks 4 and 24 had no difference between the two *** further subgroup analysis(22 in the YQPY group and 31 in the control group),the mean change in eGFR after treatment for 4 weeks was 27.39 mL/min per 1.73 m2in the YQPY group and 5.78 mL/min per1.73 m2in the placebo group,and the mean difference between groups was 21.61 mL/min per 1.73 m2(P<0.001).Thirteen(59.1%)patients in the YQPY group and 5(16.1%)in the placebo g

关键词： Chinese herbal medicine Randomized controlled trial Acute kidney injury Renal function

Colonoscopy-assisted removal of an impaction foreign body at the rectosigmoid junction: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1990-1995页

作者： Peng-Fei Zhou Jin-Gen lu jia-Dong Zhang jia-Wen Wang Department of Anorectal Surgery Longhua Hospital Shanghai University of Traditional Chinese MedicineShanghai 200000China

BACKGROUND When an anorectal foreign body is found,its composition and shape should be evaluated,and a timely and effective treatment plan should be developed based on the patient's symptoms to avoid serious complications such as intestinal perforation caused by displacement of the foreign *** SUMMARY A 54-year-old male was admitted to our outpatient clinic on June 3,2023,due to a rectal foreign body that had been embedded for more than 24 *** patient reported using a glass electrode tube to assist in the recovery of prolapsed hemorrhoids,however,the electrode tube was inadvertently inserted into the anus and could not be removed by the *** hospitalization,the patient underwent surgery,and the foreign body was dragged into the rectum with the aid of *** anus was dilated with a comb-type pulling hook and an anal fistula pulling hook to widen the anus and remove the foreign body,and the local anal symptoms were then relieved with topical *** patient was allowed to eat and drink,and an entire abdominal Computed tomography(CT)and colonoscopy were reviewed 3 d after *** revealed no foreign body residue and colonoscopy showed no metal or other residues in the colon and rectum,and no apparent intestinal tract *** The timeliness and rationality of the surgical and therapeutic options for this patient were based on a literature review of the clinical signs and conceivable conditions in such *** type,material and the potential risks of rectal foreign bodies should be considered.

关键词： Foreign body impaction Surgical therapy Rectum-sigmoid colon Colonoscopy Case report

Research progress on electronic and active site engineering of cobalt‐based electrocatalysts for oxygen evolution reaction

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Carbon Energy 2024年第8期6卷 134-165页

作者： Chuansheng He Linlin Yang jia Wang Tingting Wang jian Ju Yizhong lu Wei Chen School of Materials Science and Engineering University of JinanJinanChina Catalonia Energy Research Institute—IREC Sant Adriàde BesòsBarcelonaSpain Department of Electronic and Biomedical Engineering University of BarcelonaBarcelonaSpain Graduate School of Integrated Sciences for Life Hiroshima UniversityHigashi‐HiroshimaHiroshimaJapan Wenzhou Institute University of Chinese Academy of SciencesWenzhouChina Oujiang Lab WenzhouChina School of Chemistry and Pharmaceutical Science Guangxi Normal UniversityGuilinChina

Electrocatalytic water splitting has been identified as a potential candidate for producing clean hydrogen energy with zero carbon ***,the sluggish kinetics of oxygen evolution reaction on the anode side of the watersplitting device significantly hinders its practical ***,the efficiency of oxygen evolution processes depends greatly on the availability of cost‐effective catalysts with high activity and *** recent years,extensive theoretical and experimental studies have demonstrated that cobalt(Co)‐based nanomaterials,especially low‐dimensional Co‐based nanomaterials with a huge specific surface area and abundant unsaturated active sites,have emerged as versatile electrocatalysts for oxygen evolution reactions,and thus,great progress has been made in the rational design and synthesis of Co‐based nanomaterials for electrocatalytic oxygen evolution *** the remarkable progress in this area,in this timely review,we highlight the most recent developments in Co‐based nanomaterials relating to their dimensional control,defect regulation(conductivity),electronic structure regulation,and so ***,a brief conclusion about recent progress achieved in oxygen evolution on Co‐based nanomaterials,as well as an outlook on future research challenges,is given.

关键词： Co‐based nanomaterial dimension regulation electronic structure and active site oxygen evolution reaction